The present invention relates to a fluid pump system that accommodates a fluid pump in its cover and that delivers a conduit from the fluid pump outside the cover.
For example, in a semiconductor manufacturing process, a vacuum pump exhausts process gas and the like, which are used in a semiconductor processing device. It is not preferable that the process gas, such as arsine and silane series gas, is released into the atmosphere. Then, the process gas leaked from the vacuum pump is prevented from being released into the atmosphere in such a manner that the vacuum pump is accommodated in a cover.
When the vacuum pump is accommodated in the cover as described above, a conduit connected to the vacuum pump is delivered from the inside of the cover to the outside of the cover. Accordingly, a clearance between the conduit and the cover may be a passage through which the process gas in the cover leaks outside the cover. In a prior art, a seal member is arranged at the clearance between the cover and the conduit for shutting communication between the inside and outside of the cover through the clearance. For example, the above structure is disclosed in the page 5 and FIG. 7 in Unexamined Japanese Patent Publication No. 2002-130170.
An unwanted feature is that the structure disclosed in the Unexamined Japanese Patent Publication No. 2002-130170 directly delivers the conduit from the inside of the cover, which is a space for accommodating the vacuum pump, to the outside of the cover so that the above described single seal member serves to shut communication between the inside and outside of the cover through the clearance between the cover and the conduit. Accordingly, when the seal member degrades, the process gas in the cover possibly leaks outside the cover through the clearance between the cover and the conduit. Therefore, there is a need for a fluid pump system that efficiently prevents the fluid from leaking outside the cover.